[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 2/2] s390x/3270: handle writes of arbitrary leng
From: |
Halil Pasic |
Subject: |
Re: [Qemu-devel] [PATCH 2/2] s390x/3270: handle writes of arbitrary length |
Date: |
Thu, 21 Sep 2017 12:30:11 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 |
On 09/21/2017 11:23 AM, Cornelia Huck wrote:
> On Wed, 20 Sep 2017 19:23:14 +0200
> Halil Pasic <address@hidden> wrote:
>
>> The problem is, that the current implementation places unrealistic and
>> arbitrary constraints on the length of writes to the device (that is the
>> outbound requests), by asserting ccw.count being such that that even the
>> worst case escaped payload will fit an more or less arbitrary sized
>> buffer. Actually on protocol level there is nothing to justify such
>> a limitation.
>>
>> Another strange thing is the return value which more or less reflects
>> the size (written) after escaping instead of before escaping. This
>> is strange, because this return value is used to calculate SCSW.count.
>
> Didn't the Linux driver care about the count?
>
Maybe Jason can answer that. I did only most basic testing with my patch
applied (and basically no testing without my changes).
>From code perspective I'm sure it does for the reads. For the writes
I did not look into that.
Halil
>>
>> Let us teach 3270 how to deal with arbitrary long writes.
>>
>> Signed-off-by: Halil Pasic <address@hidden>
>> Acked-by: Christian Borntraeger <address@hidden>
>> Reviewed-by: Dong Jia Shi <address@hidden>
>> Reported-by: Jason J . Herne <address@hidden>
>> Tested-by: Jason J . Herne <address@hidden>
>> ---
>> hw/char/terminal3270.c | 30 ++++++++++++++++++------------
>> 1 file changed, 18 insertions(+), 12 deletions(-)
>
> Looks good.
>
[Qemu-devel] [PATCH 2/2] s390x/3270: handle writes of arbitrary length, Halil Pasic, 2017/09/20
Re: [Qemu-devel] [PATCH 0/2] 3270 improvements, no-reply, 2017/09/20
Re: [Qemu-devel] [PATCH 0/2] 3270 improvements, Cornelia Huck, 2017/09/21
Re: [Qemu-devel] [PATCH 0/2] 3270 improvements, Cornelia Huck, 2017/09/28